62 KEY TO THE SPECIES 



2. Apocynum cannabinuin L. (Indian Hemp). Stem and branches upright 

 or ascending ; leaves oval to oblong, sessile or short-petioled; flower-clusters erect 

 and closely many-flowered ; corolla greenish-white, with nearly erect lobes, and 

 tube not longer than the divisions of the calyx. Moist ground, 



LIII. ASCLEPIADACEiE (Milkweed Family) 



Perennial herbs with milky juice ; opposite leaves, perfect 

 regular umbellate flowers with 5 sepals, petals and stamens and 

 2 ovaries connected by the united styles and common stigma. 

 Calyx and corolla reflexed, the lobes valvate in bud ; a crown 

 of 5 hooded lobes between the petals and the tube of united fila- 

 ments which surrounds the pistil, each hood with an incurved 

 horn ; anthers adherent to the stigma, each containing a pair of 

 pollinia ; ovaries becoming a pair of large follicles containing 

 compressed seed^ bearing a tuft of long silky hair. (For fur- 

 ther details see any of the standard Manuals, Coulter, Gray, 

 Britton, etc.) 



1. ASCLEPIAS (Milkweed) 



Characters as given for the family. 



1. Asclepias speciosa Torr. (Showy Milkweed). Pale, with tomentose 

 pubescence ; stem simple, stout, 4-8 dm. high ; leaves opposite, large and thick, 

 broadly oval to ovate, 6-14 cm. long, on short petioles ; umbels 1 or more, many- 

 flowered ; corolla purple or tinged with green, its lobes oblong ; hoods lanceolate, 

 with short indexed horn ; follicles erect on deflexed pedicels, densely tomentose 

 and marked with soft spine-like processes. Frequent on moist banks. 



LIV. CONVOLVULACEiE (Moening-glort Family) 



Herbs often twining or trailing, with alternate leaves, 5 

 separate sepals, 5-lobed sympetalous corolla, 5 stamens, 1 or 2 

 styles, a superior 2- or 3-celled ovary becoming a globular few- 

 seeded pod. (See Plant Structures, p. 270 ; also p. 273, Fig. 258.) 



1. Ipomoea. Style undivided and with a knob-like stigma. 



2. Convolvulus. Style undivided, 2-cleft at apex. 



3. BvolTulus. Styles 2, distinct or nearly so, each 2-cleft at apex. 



1. IPOMCEA (Morning-gloey) 



Ours a perennial herb from an enormous deep-set root, with numerous slender 

 spreading branches (not twining), 5-12 dm. high, linear leaves and large showy 

 funnel-form purplish or crimson corolla. 



1. Ipomoea leptophylla Torr. (Bush Mornino-glory). Glabrous, freely 

 branched ; leaves 4-7 cm. long ; sepals ovate ; corolla 5-8 cm. long ; seeds pubes- 

 cent. Banks of creeks and ravines in the plains and foothills. 



